Xylem NPOPTM NPO Product Training Manual - Manual (Page 23)

PAGE 23
Commercial Water
Goulds Water Technology
INSTALLATION PROCEDURES
2.1.7 Foundation must be flat and substantial to eliminate strain when tightening bolts.
Use rubber mounts to minimize noise and vibration.
2.1.8 Tighten motor hold down bolts before connecting piping to plumbing.
3.0 SUCTION PIPING
3.1 Low static suction lift and short, direct suction piping is desired. For suction lift over 10 feet and liquid
temperatures over 120º F, consult pump performance curve for Net Positive Suction Head required.
3.2 Suction pipe must be at least as large as the suction connection of the pump. Smaller size will degrade
performance.
3.3 If larger pipe is required, an eccentric pipe reducer (with straight side up) must be installed at the pump.
3.4 Installation with pump below source of supply
3.4.1 Install full flow isolation valve in piping for inspection and maintenance.
DO NOT USE SUCTION ISOLATION VALVE TO THROTTLE PUMP.
3.5 Installation with pump above source of supply
3.5.1 Avoid air pockets. No part of piping should be higher than pump suction connection. Slope piping
upward from liquid source.
3.5.2 All joints must be airtight.
3.5.3 Foot valve to be used only if necessary for priming or to hold prime on intermittent service.
3.5.4 Suction strainer open area must be at least triple the pipe area.
3.6 Size of inlet from liquid source and minimum submergence over inlet, must be sufficient to prevent air
entering pump through vortexing. See Figures 1-4.
CAUTION
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
H
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 V
H
=
Min.
Submer
gence
in
feet
V = Velocity in feet per second
=GPM x 0.321 GPM x 0.4085
Area D 2
1.5D
min.
3.0D
min.
D D
H min.
D min.
2
---------
--------- D
H min.
D
H min.
--------- ---------
Figure 1 Figure 2
Figure 3 Figure 4